2012年1月札幌市で2人暮らしの姉妹が餓死するという事件が起こった．姉妹はなぜ生活保護を受給できなかったのだろうか．本稿の目的は，個人の合理的な選択に深く入り込んでくる「非選択的要素」を抽出しつつ，この問いを分析することにある．セン型社会的選択アプローチは，社会的決定の手続きが，個人の選好の自由な表明，パレート原理，ならびに個人的決定権の尊重といった条件をすべて満たしながらも，ある個人を死に至らしめる可能性を浮き彫りにした．潜在能力アプローチは，彼女が描きうる将来の潜在能力像は厳しいものであることを明らかにした．申請すれば，「生活」の見通しを高めることと引き換えに「自尊」の見通しを大きく狭める，しなければ後者を高めることと引き換えに前者を狭めるおそれがあった．自分の取り得る行為の選択肢が何であるかを知ることができず，生活と自尊の見通しを描くうえで十分な情報を得られずことができず，選択するうえで不可欠な一緒に思量してくれる相談相手もいなかったとしたら，「本人が申請の意思を示さなかった」ことをいったいいかなる意味で本人の自由意思の行使とみなせる．In January 2012, two sisters were found dead due to starvation in Shiroishi, Sapporo city, Japan. Why were the sisters unable to receive public assistance? The reason why one of them didn't receive public assistance was, according to the record, ʻbecause she didn't show her will to do so.' Admitting the fact, what was the real problem here? The purpose of this paper was to analyze this problem by shedding light on the ʻnon-choice elements' that deeply affect individual rational choices. Our analysis using Sen's Social Choice Approach shed light on the possibility of someone dying even as social choice procedures involving her can ostensibly satisfy all conditions of free expression of individual preferences, the Pareto Principle, and respect for the individual's decision power. Our analysis using the Capability approach has made clear that she had a very limited and miserable prospect for the future assignment of capability. By applying for public assistance, her capability will shrink in ʻself-respect' in exchange for a better prospect for ʻdecent living', while by rejecting public assistance, her capability will shrink in decent living in exchange for a better prospect for self-respect. If she didn't know what alternative actions she could choose, didn't have any reasonable prospect for her living and self-respect, and didn't have any advisor to consult, then could the fact that she ʻdidn't show her will to apply' for public assistance justify anything at all? It would be dangerous to assume that individual choices (not to apply, for example) automatically satisfy her own interests if she cares about the social conscience when forming her preference and makes a choice by accepting a social decision procedure that reflects her will correctly. These are the tentative conclusions of this paper from analyzing the starvation case using Sen's Social Choice Approach and the Capability Approach.